Acid-proof lining for boilers.



No. 744,601. PATENTED NOV. '17, 1903.

R. PANZL. AOID PROOF LINING FOR BOILERS.

APPLIOATION FILED AUG. 6- 1902.

NO MODEL. 3 SHEETS-SHEET 1.

PATENTED NOV. 17, 1903.

R. PANZL.

ACID moo? LINING FOR BOILERS.

APPLICATION FILED AUG. 6. 1902.

' no MODEL.

3 SHEETS-SHEET 2.

H0 MODEL.

PATENTED NOV. 17, 1903.

R. PANZL.

ACID PROOF LINING FOR BOILERS.

APPLICATION FILED AUG. 6. 1902.

3 SHBET8-SHEET 3.

No. 74mm.

UNITED STATES Patented November 17, 19 63.

PATENT OFFICE- ACID-PROOF LINING FOR BOILERSQ SPECIFICATION forming part of Letters Patent No. 744,601, dated November 17, 1903.v Application filed August 6, l902. .Berlal No. 11!},687. (No model.)

To all whom, it may concern: I

Be it known that I, ROMEIDIUS PANZL, of Muskegon, county of Muskegon, and State of Michigan, have invented certain new and use- 5 ful improvements in acid-proof linings of boilers, commonly called digesters', used fonpreparing wood-pulp for the manufacture of paper, and of other vessels and conduits used for storing, boiling, or conveying of cor ro rosive liquids, of which the following is a specification.

The following is a full, clear, and exact specification of my in vention, reference being had also to the accompanying drawings, wherein- Figure 1 is a vertical sectional view of a wood-pulp digester provided with lining according to my invention; Fig. 2, a cross-sectional view thereof on lines 2 2 indicated in 20 Fig. 1, and Fig. 3 a diagram showing the arrangement of the tiles.

yinvention relates to acid-proofing of vessole and conduits used for storing, boiling, or

conveying of corrosive liquids, more particularly to acid-proofing of wood-pulp digesters; and it consists of the hereinafter-described protective-linings for digesters constructed of expansible cementitious material and of acid-proof tiles cemented thereto and to each other by acid-proof mortar.

My invention relates particularly to lining of digesters used for preparing pulp for papermaking. Such pulpdigesters are constructed of iron and when used in the preparation of wood-pulp for paper-making are subjected to very high pressure and heat while filled with corrosive liquid that would rapidly destroy;

the shell if permitted to comein contact therewith. To prevent this, the interior of such digesters'is provided with a protective lining of some material which is impervious to and resists the action of the corrosive liquid. In. the United States Letters Patent toGeorge F. Russell, No. 445,235, of January 27, 1891, it is proposed to construct suchlining of commercial cement, preferably Portland, made plastic with water and applied with any suit-- able implement upon the interior of the digester-shellfl and i -the samepatent it is sug gestedthat othercement-like materials or mixtures havingsimila r propertiesor charac teristics may be.v used. sucha's. ;th e' ordinary cement mixtures, sand and Portland cement, sand and tar, and the like. I have experimented extensively with the materials stated in the Russell patent and. with a great many more similar materials, with the end in view to devise an acid-proof material for such linings which should be free from defects as such linings possess which are constructed of cement alone or of sand and Portland cement or of sand and tar and the like. In the specification of my Letters Patent No. 644,367, granted to me February 27, 1900, I have described a composition of material for lining of such digesters and the manner of using them. The results of my experiments have since been confirmed in every respect in practical useof myinvention. I have since found through the manifold practical applications of my said invention that a lining construct ed of such compositionof material is absolutely proof against and impermeable by any corrosive liquid and practically indestructible. There is yet, however, the difiiculty to be overcome arising from the circumstance that the pulp-digesting process requires a high degree of heat andhigh pressure in the interior of the digesters. The heat acting upon the metallic shell of the digester causes it to expand, and if the material of the lining does not expand correspondingly the combined effect of the heat and pressure often results in tearingand breaking the lining or separating it in some places from the shell. The pressure within the digester is .so great that the corrosive liquid is forced almost immediately through the most minute crevices in the lining and coming in contact with the material of the shell destroys it. Having experimen ted with the object in view to obviate this ditficulty in the lining of the digesters, I have discovered the hereinafter-described composition of. material for suchlinings that does notdrawor crack when applied to the digesters, being in that respect equal to the composition of material set forth in my aforesaid 644,367, is also wholly inditfe'rent and imper vions to such corrosive-liquids as are used in' pulp-digesters, and in addition thereto possessesthe qualityof expanding in a slightlyhigher degree than iron. The composition is Letters Patent No.

also abad conductor of heat. When-subject cos b s ed to heat and pressure, as it is under the conditions when used as lining for pulp-digesters, the composition is rendered to some extent yielding and expands, and while its density and imperviousness to such corrosive liquids remain'unimpaired it adjusts itself to the expanded shell of the digester and does not bulge or separate from the shell when the latter contracts. This composition is made up of calcined chamotte, slag, burnt cement, and coal-tar pulverized and mixed dry, an equal part, measured by volume, being used of each, and made into a mortar by adding thereto liquid silicate of soda of not less than 30 nor more that 45 Baum. The dry ingredients can be mixed in larger quantities; butonlya smallquantityof the mortar should be made at one time, as required for immediate use. This mortar is then immediately used in making the lining. The boiler must be moderately heated before and while the lining is being applied. The best results are obtained if two or three workmen cooperate, one constantly preparing small quantities of the mortar and the others applying the same. The mortar hardens rapidly, and care must be taken that each successive addition of lining is applied before the preceding part is hardened. The inside of the boiler or digester to whichthe lining is applied must be free from rust and absolutely clean. The lining need not be more than one inch thick.

In the course of my experiments I subjected the lining, constructed of the stated ingredient-s as hereinbefore described, to most severe tests and found that one inch thickness thereof is sufilcient under any conditions to protect the shell of the digester from the effects of concentrated corrosive chemicals and that it does not deteriorate when exposed to heat and pressure. largely exceeding that required to be maintained in digesting the pulp by the sulfite process. Though the liningis sufiiciently hard to withstand the mechanical action of the process, it is also expansible,and when subjected to heat and pressure expands nearly coextensively with the iron shellA of the digester. To protect this lin-.

Inga against abrasion or mechanical injury, I make a super-lining of tiles arranged as shown in the accompanying drawings. Tiles 1) and b are preferably made of chamotte mixed with coarse sand or crushed quartz compressd and burned. For'aflixing the tiles upon the- .lining and for joining the tiles together and upon each other the same material may be used as hereinbefore specified for the plastic layer or a mortar c, composed of the following ingredients, the parts being measured by volume: seven parts pulverized chamotte or crushed fire-bricks, three parts of burnt cement, and such quantity of silicate of soda of about 30 to 45 Baum as is'required to mix the ingredients into a plastic mass, like ordinary mortar used in plastering. This mortar is prepared in small quantities-and is applied to the bricks or tiles on the back andmaking two layers of such 'ing them as herein shown. and described consists in that-if any joint should break no lea-k all edges thereof. Thetiles' must be pressed hard upon the lining to expel any air-bubbles that may be caught between the lining and the tile.-' The mortar (designated d in the diately after applying a strip of the plastic layer the tiles are applied thereon,andithus the work of lining the digester is proceeded with, beginning at the bottom outlet'thereof, successively toward the top. In digesters where the process does not require a very high pressure one layer of such tiles secured to the expansible cemen titious material and to each other by such acid-proof mortar as herein described is sufficient. Such lining will sufiiciently protect the shell of the digester, even if the cementitious expansible material be not absolutely impervious to or proof against acid. The plastic layer being yielding and expansible and adhering to both the shell'and to the mortar joining it with the tiles, acts as a yielding or filling support for the layer constructed of the acid-proof tiles and of the acidp'roof mortar. By reason of its being expansible it prevents the cracking or tearing of this layer. It also acts as an insulator, protecting the shell against the effects of the heat, and therefore reduces, if not wholly prevents, the expansion of the shell; but if the digester is to be used in a process where a high pressure is required it is preferable to use more than one layer of tiles, secured to the plastic layer and to each other by the. acid-proof mortar set forth herein. When more than onelayer of tiles are used, the rows of. tiles are so arranged that the joints of each preceding layer are covered up by the tiles of the succeeding layer. Such arrangementof the tiles is shown in the liningillustrated in the drawings. Two layers of such tiles are applied. The arrangement of these tiles is shown in Fig. 3. It will be seen there that the tiles are all univform in shape and size and that while in one (the lower) layer the tiles Tare arranged with their longest dimensions from bottom to top the tiles 0f the other layer are arranged with their longest dimensions from left to right or horizontally. The dotted lines indicate the joints of the tiles in the first layer where they are covered by the tiles of the second layer. From this illustration it will be seen that by this simple arrangement the joints'of the first layer are wholly covered and protected by the tiles of the second layer. The advantage of tiles and arrangage would occur in the lining, because the break could not-extend beyond the layer in which the break occurred.

I claim as my invention- 2. An acid-proof lining for vessels and con-- duits used for storing", boiling or conveying of corrosive liquids, made up of a continuous l layer of acid-proof plastic material composed of calcined chamotte, slag, burnt cement, coal-tar and liquid silicate of soda, applied upon the interior of such vessels or conduits,

and of acid-proof tiles cemented togetherand to the layer of acid proofi plastic material.-

'3. An acid-proof lining for vessels and conduits used for storing, boiling or conveying of corrosive liquids, made up of a layer of plastic material, composed of calcined chamotte, slag, burnt cement,coal-tar, and liquid silicate of soda, mixed together as herein set forth, and applied upon the interior of such vessels or conduits; a. layer of acid'proof mortar, and a layer of acid-proof tiles, cemented together by acid-proof mortar.

An acid-proot-lining for vessels and conduits used ,for storing, boiling or conveying of corrosive liquids, composed of a layer of plastic, cementitious material, yielding and expansible when subjected to heat and pressure; a layer of acid-proof mortar composed of pulverized chamotte, burnt cement, and

silicate of soda, and of a layer of acid-proof tiles, cemented together by acid-proof mortar.

5'. An acid-proof lining for vessels and conduits used for storing, boiling or conveying of corrosive liquids, composed ofa layer of plastic cementitious material, yielding and expansible when subjected to heat and pressure; of layers of acid-proof tiles, and of layers of acid-proof mortar made up of pulverized chamotte, burnt cement, and silicate of soda, the layers of acid-proof mortar being interposed between the layer of the yielding, expansible material and the first layer of tiles, between the successive layers of tiles,

and the adjoining surfaces of the tiles in each layer being cemented together by acid-proof mortar.

6. An acid-proof lining for vessels and conduits used for storing, boiling or conveying of corrosive liquids, made up of a layer of acid-proof plastic material composed of calcined chamotte, slag, burnt cement, coal-tar, and liquid silicate of soda mixed together, substantially as herein set forth, and applied upon the interior of such vessels or conduits; and of successive layers of acid-proof tiles cemented together by acid-proof mortar, the tiles of each succeeding layer being laid over the joints of the tiles of the preceding layer.

ROMEDIUS PANZL. Witnesses: ERNST HEUTSCHEL, W. H. N EUTON. 

